Which kind of metrics are associated with the function deriv()?

Thederiv()function in PromQL calculates theper-second derivativeof a time series using linear regression over the provided time range. It estimates theinstantaneous rate of changefor metrics that can both increase and decrease — which are typicallygauges.

Because counters can only increase (except when reset), rate() or increase() functions are more appropriate for them. deriv() is used to identify trends in fluctuating metrics like CPU temperature, memory utilization, or queue depth, where values rise and fall continuously.

In contrast,summariesandhistogramsconsist of multiple sub-metrics (e.g., _count, _sum, _bucket) and are not directly suited for derivative calculation without decomposition.